1. Field
The present disclosure relates to network monitoring and troubleshooting. More specifically, the present disclosure relates to a method for detecting reachability in a network implementing the Transparent Interconnection of Lots of Links (TRILL) protocol.
2. Related Art
As more mission-critical applications are being implemented in data communication networks, high-availability operation is becoming progressively more important as a value proposition for network architects. It is often desirable to divide a conventional aggregated link (from one device to another) among multiple network devices, such that a node failure or link failure would not affect the operation of the multi-homed device.
Meanwhile, layer-2 (e.g., Ethernet) networking technologies continue to evolve. More routing-like functionalities, which have traditionally been the characteristics of layer-3 (e.g., IP) networks, are migrating into layer-2. Notably, the recent development of the Transparent Interconnection of Lots of Links (TRILL) protocol allows Ethernet switches to function more like routing devices. TRILL overcomes the inherent inefficiency of the conventional spanning tree protocol, which forces layer-2 switches to be coupled in a logical spanning-tree topology to avoid looping. TRILL allows routing bridges (RBridges) to be coupled in an arbitrary topology without the risk of looping by implementing routing functions in switches and including a hop count in the TRILL header. Like any other type of network, a TRILL network needs to be monitored and maintained to ensure its proper operation. However, at present, TRILL networks lack many of the network control and management functions available in layer-3 networks.